Off Topic — HabitableZone

Off Topic » in reply to re: Mass & Energy, Planet size, etc.

Score one for Wikipedia...
Michael Gmirkin — (archived)

Actually, I think wikipedia agrees with me, or I with them. Anyway, they put it better in their article on the definition of Force:

"Instead of a force, the mathematically equivalent concept of a potential energy field can be used for convenience. For instance, the gravitational force acting upon a body can be seen as the action of the gravitational field that is present at the body's location. Restating mathematically the definition of energy (via definition of work), a potential field U(r) is defined as that field whose gradient is equal and opposite to the force produced at every point ... Forces can be classified as conservative or nonconservative. Conservative forces are equivalent to the gradient of a potential, and include gravity, electromagnetic force, and spring force."

I think that's kind of what I was trying to utter with my beach ball analogy... The potential energy is a gradient varying with distance from the center of mass. Likely in an "Intensity" formulation, which is a geometrical sphere under over-idealized situations. The further the gradient is penetrated by an interloping object, deforming the sphere elastically, the greater the potential energy that is encountered b ythe interloper. Eventually the interloper either reaches the center of mass and effectively moves the object, or it encounters sufficient resistance to halt its progress, reach that "equal and opposite force," and then most likely be accelerated in the opposite direction by the kinetic energy newly converted into potential energy in the object being acted upon by the interloper... Kind of like the beach ball expelling the rock that hits it.

That's what I was getting at to begin with, or trying to... :) Woohoo! I feel less crazy now. But only marginally. Hehe...

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